This invention relates generally to lost core molding machines and, more specifically, to a manifold assembly which minimizes degradation of the molten material chamber.
Conventional lost core molding processes require the use of a molding machine manifold to communicate a heated fluid within the manifold. The heated fluid within the manifold maintains the core cast material such as tin bismuth alloy in a molten state. The molten alloy can then be injected through a nozzle and into a mold tool.
The molten metal is a highly abrasive fluid. In some applications, the molten alloy that is used in the molding process causes conventional manifold fluid passageways and nozzles to deteriorate over a relatively short period of time thereby necessitating frequent maintenance. Further problems may be experienced if the manifold ineffectively or unevenly heats the molten alloy. Partially or unevenly heated alloy cools within the manifold passages. The cooled alloy expands and inhibits further flow of the alloy.
Accordingly, it is desirable to provide a lost core molding manifold which maintains even heat and flow of the core cast material such that maintenance requirements are decreased.
The lost core molding assembly according to the present invention provides for the improved the handling of the molten alloy and reducing mold assembly maintenance. A manifold is mounted to a mold to inject the molten alloy such as Tin Bismuth to a mold cavity therein. The manifold is preferably manufactured of a heat resistant steel such as T-15 steel which is a high speed steel with a tungsten additive. The T-15 steel minimizes adherence between the tin bismuth and manifold. Oxidation and build-up is thereby minimized and operation time between maintenance is improved.
The molten alloy is received into the manifold at an alloy input from an alloy source.
The manifold directs the molten alloy to the nozzles where it is then injected into the mold cavity.
The manifold receives a heated fluid from a source and circulates the heated fluid through a heated fluid passage. The present invention provides a heated fluid passage arrangement which assures that the heated fluid maintains the molten alloy in an even molten condition thereby reducing degradation of the molten alloy prior to injection into the mold.
The present invention therefore provides a lost core molding manifold which maintains even heat and flow of the core cast material such that maintenance requirements are decreased.